Recently, a Fin type MOSFET (hereinafter referred to as a “FinFET”) has been proposed in order to establish a balance between improvement of integration of a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) and an increase in on-current. In the FinFET, projected fins each of which extends in one direction are formed on an upper surface of a semiconductor substrate, and gate electrodes each of which extends in another direction are formed so as to straddle the fins. Therefore, in the fin, an outer periphery surrounded by the gate electrodes constitutes a channel region, and a channel width can be increased without enlarging an element area.